Blackfin: adi boards: drop old ELF define

This define isn't used anywhere anymore, so punt it.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

include/configs/bfin_adi_common.h

@@ -85,7 +85,6 @@
 # define CONFIG_CMD_CACHE
 # define CONFIG_CMD_CPLBINFO
 # define CONFIG_CMD_ELF
-# define CONFIG_ELF_SIMPLE_LOAD
 # define CONFIG_CMD_GPIO
 # define CONFIG_CMD_KGDB
 # define CONFIG_CMD_REGINFO